Plating and method of accomplishing same



i No Drawing.

Patented Jan. 27, 1925.- v gia PATENT 9 JAMES A. MI URPHY, 0 LANSING, MICHIGAN.

unlTEn STATES,

rLA'rmG AND Mnrno'n To all whom it may concern:

Be it known that I, JAMES A. MURPHY, a citizen of the United States, residing at Lansing, in the county of Ingham and State of Michigan; have invented certain new' and useful Improvements in Plating and Methods of Accomplishing Same, of Which the following is a specification.

The object of my inventidn is to provide an improved'plating and method of accomplishing same. 1 v

A furtherobject of my invention is to provide a plating solution, which may be used in connection with the process of nickel plating which will eliminate a considerable part of the labor required for producing nickel plating, which will chea'pen the cost thereof, which will decrease the timeneces- -sary for accomplishing the plating, which will eliminate one ordinary operation, and

which will enable me to secure a coating of un1form thicknessand texture.

ln-connectiou-with the nickel plating process with which l have been familiar, and where it has been desired to secure a very high or the highest class of nickel" plate finish on brass or ferrous articles, it has been customary to thoroughly clean the articles to be plated, then the articles if of a ferrous nature are copper plated, then polished. then nickel plated, and thenthe article is again buffed or polished, some polishing material being used in connection with the last bufling or polishing operation, which is designed to give theplated article what is termed color,. It is a further object of my invention to eliminate this last polishing or ,color operation in connection with nickel plating as the polishing pperation or bufling. tends ,to wear through the coating of plating at the. corners or edges of theplated articles materially, thereby materially lessening the durability of the plate,

as the'greatestwear on such articles ondi- ,narily comes on the corners or edges. c A further object of my invention is to J 1,524,448 FFICE.

or Acoo vrrLIsnmo SAME.

Application filed April 26, 1923. Serial No. 634,861.

prepare the materials to be placed so that they are chemically clean. One way 1114 which this may be accomplished consists of the following process: First, dipping the 'aI't-icles in a strongcaustic lye solution; second, washing the articles by dipping them in a warm water bath of from 100 to 150 degrees Fahrenheit temperature; third, dipping the articles in an acid solution consisting of muria tic acid and water; fourth, washing the articles by dipping them in cool water, such for instance, as from 40 to degrees Fahrenheit; fifth, immersing the articles for from one to three minutes in a 7. cleaning device, using electrolysis and having an alkali solution-therein, such for instance, as soda ash or tri-sodium solution "therein; sixth, rinsing in cold water or cold alkali solution with a trace of cyanide of potassium; eighth, dip in a cold-solution of cyanide of potassium; ninth, rinse in cold water.

The tri-sodium solution above mentioned may be made of tri-sodium phosphate and water (Na PU plus 12 11 0).

It will be understood that this method of cleaning is merelyillustra tive, and any suitable method of cleaning Which will give a chemically cleam surface maybe used.

If the articles to be nickel plated are to be of a ferrous nature, it is desirable to first 9e copper plate them, which may be done by immersing them in a copper solution in an electro plating. tank, andplating for a periodrof time necessary to deposit a copper coating of the desired thickness.

Following the copper plating operations,

if thearticles areof a ferrous materialbr following the cleaning operation, if the articles are of a non-ferrous material, these articles are burnished or buifed on the surface to which it is desired to give a bright nickel finish. The extent-of this burnishing or buffing process is dependent upon the smoothness of the final finish, which it is desired to produce, and may of .course be continued until. the metal has reached the desired smoothness.

- Followingthe burnishing or bufling processdescribed the articles are immersed-in a nickel lating tank, containing the following so ution: To onegallon of water add; 8 ounces of nickel ammonium sulphate be proportionately lengthened.

(NiSO (NH-Q S. O. lus 6H O), 4 ounces nickel sulphate (NiS plus 7H O), ounce salammoniac, 3 penny weights cadium chloride, 1% ounce glycerine.

The articles to be nickel plated are suspended in this solution which should be held in a temperature of from 70 to 80degrees Fahrenheit, and should be maintained at a specific gravity of from 6 to 8 B. The specific gravity can be maintained for successive plating operations which tend to reduce same, by adding the metal parts of the solution thereto in the same proportions in the current voltage used, the amperage used. and the strength of the solution. If a very heavy coating is desired, the time is proportionatelylengthy and if a. comparatively light coating is desired, the time is shortened. With a large amount of material in the tank atthe same time; the time has to What-ever the time may be that the article is llowed to remain in the solution, it will b bright and have a very high lustre at the-time, it is removed from the solution, and this lustre will be maintainedwithout furthenpolish ing or buffing operations As soonas the article is removed from the plating baths, it is rinsed in cold water and dipped in a two to one solution of niuriatic acid: then rinsed in cold water and then. dipped in hot water mixed with Whale oil or whale oil soap, which permits the finish to dry without being spotted, and at the same time preserves the finish and imparts the color desired thereto.

Among the manyadvantages arising from my improved process, the main. one is the fact that the buffing or polishing operation, which follows the plating operation inthe ordinary nickel plating process with which I am familiar, has been eliminated in connection with the use of my improved process. whereby the plating will be just as thick at the corners or. edges of the plated articles as it is on the plain surface thereof, so that a plate of a given thick ness will wear a proportionately longer time. 'Of course further advantages result in the decrease in cost due to the elimination.of this final polishing or bufiing operation. A second main advantage of the use of my solution, resides in the fact that I am enabled to cut down the time of the immersion of the articles in the nickel plating solution to about half that necessary for other solutions with which I have been familiar.

These advantages in connection with the saving of time, labor and cost, together with the improvement in the plating secured, do not in any way effect the desirability of the appearanceof the plate. In fact, the color and the finish of the samples WhlCh I have made up by-my improved process are fully equal to any nickel plated articles which I have ever seen.

The composition of the solution matter is varied somewhat: For instance, the proportion of cadmium chloride may be varied from oneto six pennyweights in the formula herein given. The proportions of the single and double sulphate nickel salts may be varied both in regard to each other, and in regard to the balance of the formula by considerable quantities without departing from my invention. Any suitable substances may be substituted for the bora cic acid and the 1111111211310.21C1(l, which Wlll' accomplish the same result, and the proportions thereof variedas much as 35% for instance, sulphuric acid may be substituted for muriatic acid and sulphate of aluminum for boracic acid.

Having thus described myinvention, what I claim as new, and desire to secure by Letters-Patent, is:

1. A solution for a, nickel plating tank comprising the followingingredients in the proportions set forth, to one gallon of water, add from 5 to 12 ounces of nickel ammonium sulphate, 1 to 8 ounces nickel sulphate, to 4 ounces boracic acid, ounce sal-ammoniac 1 to 8 pennyweights cadmium chloride, to 2 ounces glycerine.

2. A solution for a nickel plating. tank comprising the following ingredients in the proportions set forth, to one gallon of water, add 8 ounces of nickel ammonium sulphate, 4 ounces nickel sulphate, 2 ounces boracic acid, ounce sal-ammoniac, 3 pennyweights cadmium chloride, 1 ounce glycerine. r

In testimony whereof I affix my signature.

' JAMES A. MURPHY. 

